Inorganic plastic cements such as magnesium oxychloride and oxysulfate plastic cements have been described in numerous patents. Cements of these types are highly desirable if they can be properly molded, and remain truly insoluble since they possess excellent fire retardant properties. Numerous applications of molded oxychloride cement parts for use in fire rich areas such as boat parts, building panels and the like suggest themselves. Difficulty has been encountered however in the preparation of molded plastic oxychloride cement parts due to their tendency of efflorescence.
Typical cements are described in the prior art in U.S. Pat. Nos. 3,220,077 and 2,939,799. While these patents readily produce plastic oxychloride cements, it has been found that molded parts made from cements using the prior art teachings have often led to finished parts that effloresce rendering them less than satisfactory.